1.1 --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
     1.2 +++ b/src/comm.c	Wed Mar 07 06:11:51 2012 +0200
     1.3 @@ -0,0 +1,187 @@
     1.4 +/*
     1.5 +gbasys - a gameboy advance hardware abstraction library
     1.6 +Copyright (C) 2005-2012  John Tsiombikas <nuclear@member.fsf.org>
     1.7 +
     1.8 +This program is free software: you can redistribute it and/or modify
     1.9 +it under the terms of the GNU General Public License as published by
    1.10 +the Free Software Foundation, either version 3 of the License, or
    1.11 +(at your option) any later version.
    1.12 +
    1.13 +This program is distributed in the hope that it will be useful,
    1.14 +but WITHOUT ANY WARRANTY; without even the implied warranty of
    1.15 +MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    1.16 +GNU General Public License for more details.
    1.17 +
    1.18 +You should have received a copy of the GNU General Public License
    1.19 +along with this program.  If not, see <http://www.gnu.org/licenses/>.
    1.20 +*/
    1.21 +
    1.22 +#include "comm.h"
    1.23 +#include "error.h"
    1.24 +#include "signal.h"
    1.25 +#include "intr.h"
    1.26 +
    1.27 +#define REG_SIODATA32	*((volatile unsigned short*)0x4000120)
    1.28 +#define REG_SIOCNT		*((volatile unsigned short*)0x4000128)
    1.29 +#define REG_SIODATA8	*((volatile unsigned short*)0x400012a)
    1.30 +#define REG_RCNT		*((volatile unsigned short*)0x4000134)
    1.31 +
    1.32 +/* REG_SIOCNT bits */
    1.33 +#define SIOCNT_CLK_INTERN		(1 << 0)
    1.34 +#define SIOCNT_CLK_2MHZ			(1 << 1)
    1.35 +#define SIOCNT_RECV_ENABLE		(1 << 2)
    1.36 +#define SIOCNT_SEND_ENABLE		(1 << 3)
    1.37 +#define SIOCNT_START			(1 << 7)
    1.38 +#define SIOCNT_XFER_LEN			(1 << 12)
    1.39 +#define SIOCNT_INT_ENABLE		(1 << 14)
    1.40 +
    1.41 +/* only in 16bit multi player mode */
    1.42 +#define SIOCNT_BAUD_38400		1
    1.43 +#define SIOCNT_BAUD_57600		2
    1.44 +#define SIOCNT_BAUD_115200		3
    1.45 +#define SIOCNT_SI_STATUS		(1 << 2)
    1.46 +#define SIOCNT_SD_STATUS		(1 << 3)
    1.47 +#define SIOCNT_SLAVE1			(1 << 4)
    1.48 +#define SIOCNT_SLAVE2			(2 << 4)
    1.49 +#define SIOCNT_SLAVE3			(3 << 4)
    1.50 +#define SIOCNT_ERROR			(1 << 6)
    1.51 +
    1.52 +/* REG_RCNT bits */
    1.53 +#define RCNT_GPIO_DATA_MASK		0x000f
    1.54 +#define RCNT_GPIO_DIR_MASK		0x00f0
    1.55 +#define RCNT_GPIO_INT_ENABLE	(1 << 8)
    1.56 +#define RCNT_MODE_GPIO			0x8000
    1.57 +#define RCNT_MODE_JOYBUS		0xc000
    1.58 +
    1.59 +
    1.60 +static void setup_sio(int bits, int ms);
    1.61 +static void setup_gpio(void);
    1.62 +static void comm_intr(void);
    1.63 +
    1.64 +static int sio_bits, sio_master;
    1.65 +static void *sio_buf;
    1.66 +
    1.67 +
    1.68 +void comm_setup(int mode)
    1.69 +{
    1.70 +	int master = 0;
    1.71 +
    1.72 +	mask(INTR_COMM);
    1.73 +	interrupt(INTR_COMM, comm_intr);
    1.74 +	unmask(INTR_COMM);
    1.75 +
    1.76 +	switch(mode) {
    1.77 +	case COMM_SIO8_MASTER:
    1.78 +		master = 1;
    1.79 +	case COMM_SIO8_SLAVE:
    1.80 +		setup_sio(8, master);
    1.81 +		break;
    1.82 +
    1.83 +	case COMM_SIO32_MASTER:
    1.84 +		master = 1;
    1.85 +	case COMM_SIO32_SLAVE:
    1.86 +		setup_sio(32, master);
    1.87 +		break;
    1.88 +
    1.89 +	case COMM_GPIO:
    1.90 +		setup_gpio();
    1.91 +		break;
    1.92 +
    1.93 +	default:
    1.94 +		panic("unimplemented comm mode\n");
    1.95 +	}
    1.96 +}
    1.97 +
    1.98 +static void setup_sio(int bits, int ms)
    1.99 +{
   1.100 +	REG_RCNT = 0;	/* serial mode */
   1.101 +
   1.102 +	sio_bits = bits;
   1.103 +	sio_master = ms;
   1.104 +}
   1.105 +
   1.106 +void sio_transfer(void *in, const void *out)
   1.107 +{
   1.108 +	/* load outgoing data */
   1.109 +	if(sio_bits <= 8) {
   1.110 +		REG_SIODATA8 = *(unsigned char*)out;
   1.111 +	} else {
   1.112 +		REG_SIODATA32 = *(unsigned long*)out;
   1.113 +	}
   1.114 +	sio_buf = in;
   1.115 +
   1.116 +	/* IE=1, external clock, send enable */
   1.117 +	REG_SIOCNT = SIOCNT_INT_ENABLE | SIOCNT_SEND_ENABLE;
   1.118 +
   1.119 +	/* start transfer */
   1.120 +	REG_SIOCNT |= SIOCNT_START;
   1.121 +
   1.122 +	/* wait until the transfer is complete */
   1.123 +	while(REG_SIOCNT & SIOCNT_START);
   1.124 +}
   1.125 +
   1.126 +void sio_transfer_async(void *in, const void *out)
   1.127 +{
   1.128 +	/* load outgoing data */
   1.129 +	if(sio_bits <= 8) {
   1.130 +		REG_SIODATA8 = *(unsigned char*)out;
   1.131 +	} else {
   1.132 +		REG_SIODATA32 = *(unsigned long*)out;
   1.133 +	}
   1.134 +	sio_buf = in;
   1.135 +
   1.136 +	/* IE=1, external clock, send enable */
   1.137 +	REG_SIOCNT = SIOCNT_INT_ENABLE | SIOCNT_SEND_ENABLE;
   1.138 +
   1.139 +	/* start transfer */
   1.140 +	REG_SIOCNT |= SIOCNT_START;
   1.141 +}
   1.142 +
   1.143 +
   1.144 +static void setup_gpio(void)
   1.145 +{
   1.146 +	REG_RCNT = RCNT_MODE_GPIO | RCNT_GPIO_INT_ENABLE;
   1.147 +}
   1.148 +
   1.149 +void gpio_dir(int dir_so, int dir_si, int dir_sd, int dir_sc)
   1.150 +{
   1.151 +	unsigned char mask;
   1.152 +
   1.153 +	mask = ((dir_so & 1) << 7) | ((dir_si & 1) << 6) | ((dir_sd & 1) << 5) |
   1.154 +		((dir_sc & 1) << 4);
   1.155 +	gpio_dir_mask(mask);
   1.156 +}
   1.157 +
   1.158 +void gpio_dir_mask(unsigned char dir)
   1.159 +{
   1.160 +	REG_RCNT = (REG_RCNT & 0xff0f) | ((dir & 0xf) << 4);
   1.161 +}
   1.162 +
   1.163 +void gpio_set(unsigned char val)
   1.164 +{
   1.165 +	REG_RCNT = (REG_RCNT & 0xfff0) | (val & 0xf);
   1.166 +}
   1.167 +
   1.168 +unsigned char gpio_get(void)
   1.169 +{
   1.170 +	return REG_RCNT & 0xf;
   1.171 +}
   1.172 +
   1.173 +static void comm_intr(void)
   1.174 +{
   1.175 +	if(sio_buf) {
   1.176 +		if(REG_SIOCNT & SIOCNT_START) {
   1.177 +			panic("asio: interrupt with start bit == 1");
   1.178 +		}
   1.179 +		if(sio_bits <= 8) {
   1.180 +			*(unsigned char*)sio_buf = REG_SIODATA8;
   1.181 +		} else {
   1.182 +			*(unsigned long*)sio_buf = REG_SIODATA32;
   1.183 +		}
   1.184 +		sio_buf = 0;
   1.185 +	}
   1.186 +
   1.187 +	if(signal_func(SIGIO)) {
   1.188 +		raise(SIGIO);
   1.189 +	}
   1.190 +}